In vivo laser speckle contrast imaging of microvascular blood perfusion using a chip-on-tip camera

Lukas Markwalder; Rodney Gush; Faisel Khan; Colin E Murdoch; Nikola Krstajić

doi:10.1016/j.isci.2024.109077

In vivo laser speckle contrast imaging of microvascular blood perfusion using a chip-on-tip camera

iScience. 2024 Feb 1;27(3):109077. doi: 10.1016/j.isci.2024.109077. eCollection 2024 Mar 15.

Authors

Lukas Markwalder¹, Rodney Gush², Faisel Khan¹, Colin E Murdoch¹, Nikola Krstajić³

Affiliations

¹ Systems Medicine, School of Medicine, University of Dundee, Ninewells Hospital & Medical School, DD1 9SY Dundee, UK.
² Moor Instruments, Millwey Rise Industrial Estate, Weycroft Avenue, EX13 5HU Axminster, UK.
³ School of Science and Engineering, Fulton Building, University of Dundee, DD1 4HN Dundee, UK.

Abstract

Laser speckle contrast imaging (LSCI) is an important non-invasive capability for real-time imaging for tissue-perfusion assessment. Yet, the size and weight of current clinical standard LSCI instrumentation restricts usage to mainly peripheral skin perfusion. Miniaturization of LSCI could enable hand-held instrumentation to image internal organ/tissue to produce accurate speckle-perfusion maps. We characterized a 1mm² chip-on-tip camera for LSCI of blood perfusion in vivo and with a flow model. A dedicated optical setup was built to compare chip-on-tip camera to a high specification reference camera (GS3) for LSCI. We compared LSCI performance using a calibration standard and a flow phantom. Subsequently the camera assessed placenta perfusion in a small animal model. Lastly, a human study was conducted on the perfusion in fingertips of 13-volunteers. We demonstrate that the chip-on-tip camera can perform wide-field, in vivo, LSCI of tissue perfusion with the ability to measure physiological blood flow changes comparable with a standard reference camera.

Keywords: Biodevices; Bioengineering; Devices; Materials science; Medical device.